Getting started with answer machine detection:

1. Detecting voicemail

Many companies detect voicemail by using beep detection. We do not. We think it is not the best way. We detect voicemail using heuristic algorithms which are based on the tone of voice, the speed of spoken words, etc.

This detection usually takes 3 to 5 seconds and usually has an accuracy of 60-75% which is on par with the industry standards. You can enable AMD at Plivo using our outbound call API itself with machine_detection and machine_detection_time as parameters. you can check out details on our outbound call API page.

2. Leaving the message after the beep

Based on whether it is a voicemail or human, the app can either leave a recording or connect to an agent. Some systems trigger this hook based on beep. We trigger it based on a certain silence threshold for we have seen better results with it. This is what the minSilence parameter is useful for. It will pause further execution of the call till there is defined silence as per the threshold.